I recently had an accident on my electric scooter. I was thrown off on to the paved roadway. 
I struck the ground hard, breaking my left clavicle. 
Not until I returned from the hospital, did I look at my helmut. I was surprised when I seen the actual contact point where my head (inside the helmut) contacted the pavement. 
The Helmut was broken by the impact ( I have images), but my head was not broken. 
The Helmut did it's job! Didn't help my clavicle, I am grateful for this piece of safety equipment. 
Now I'm going out to get my replacement helmut, although I won't be riding again until I'm healed!